#include"ThreadCache.h"
#include"CentralCache.h"

void* ThreadCache::FetchFromCentralCache(size_t index,size_t size)
{
	size_t batchNum = min(_freeLists[index].MaxSize(), sizeClass::NumMoveSize(size));
	if (_freeLists[index].MaxSize() == batchNum)
	{
		_freeLists[index].MaxSize() += 1;
	}

	void* start = nullptr;
	void* end = nullptr;
	size_t actualNum= CentralCache::GetInstance()->FetchRangeObj(start, end, batchNum, size);
	assert(actualNum >= 1);
	if (actualNum == 1)
	{
		assert(start == end);
		return start;
	}
	else
	{
		_freeLists[index].PushRange(NextObj(start), end,actualNum-1);
		return start;
	}
}

void* ThreadCache::Allocate(size_t size)
{
	assert(size <=MAX_BYTES);
	size_t alignSize = sizeClass::RoundUp(size);
	size_t index = sizeClass::Index(size);

	if (!_freeLists[index].Empty())
	{
		return _freeLists[index].Pop();
	}
	else
	{
		return FetchFromCentralCache(index, alignSize);
	}
}

void ThreadCache::Deallocate(void* ptr, size_t size)
{
	assert(ptr);
	assert(size <=MAX_BYTES);
	size_t index = sizeClass::Index(size);
	
	_freeLists[index].Push(ptr);

	if (_freeLists[index].Size() >=_freeLists[index].MaxSize())
	{
		ListTooLong(_freeLists[index], size);
	}

}

void ThreadCache::ListTooLong(FreeList& list, size_t size)
{
	void* start = nullptr;
	void* end = nullptr;
	list.PopRange(start, end, list.MaxSize());
	CentralCache::GetInstance()->ReleaseListToSpans(start, size);
}

